| A case study of how ACAS II works...
posted 13 March 2017 in Category:Accidents and Incidents
On 26 May 2013, an aircraft in Swiss Class 'C' airspace received a TCAS 'Level Off' RA against a 737 above after being inadvertently given an incorrect climb clearance by ATC. The opposing higher-altitude 737 began a coordinated RA climb from level flight and this triggered a second conflict with another 737 also in the cruise 1000 feet above which resulted in coordinated TCAS RAs for both these aircraft. Correct response to all RAs resulted in resolution of both conflicts.